We have a pump with Rubber expansion joint but we don’t have any values for the stiffness and the vendor is not responding How can I model it?

Note: Movements are provided in the data sheet as following:
Axial (mm) 10
Lateral (mm) 25
Angular (mm) 0

The vendor has to give you stiffnesses, otherwise you can't model it. If the vendor is unresponsive, buy the joint from someone else.

Hi,

Just a word of warning about rubber bellows, they have very low service life (approx. 10 years if you are lucky, and plants are normally designed for a service life of at least 20 years) and are not very suitable for service outside in the open and need regular attention, so avoid rubber bellows like the plague! use metal alloy bellows if you can , in my experience they tend to be about the same price.